$10 Elecfreaks WuKong 2040 raspberry pi pico and Pico WEasily connect 4 motors, 12 servos, or any combination of sensors and common electronics. But there are two things that make this one stand out from the crowd. First, there is a large 18650 battery holder on the top of the board. This means you can power your project for up to an hour and charge the battery using the onboard micro USB port. Next, under the board is a Lego compatible frame that can be used to integrate the board and Pico into your Lego based electronics project.
All of these features are great, but do they work? Can you build something with them? To know you’ve put them on the bench and tested them.
Wukong 2040 specifications
| pico compatibility | Raspberry Pi Pico, Raspberry Pi Pico W, and other boards that share pinouts |
|---|---|
| GPIOs | SVG (Signal, Voltage Gnd) pins for GPIO 0,1,2,3,4,5,6,7,8,16,17,26,27,28 |
| motor connection | |
| M1: GPIO 20, 21 | |
| M2: GPIO 10, 11 | |
| M3: GPIO12, 13 | |
| M4: GPIO14, 15 | |
| button | |
| Answer: GPIO18 | |
| B: GPIO19 | |
| Neopixel / WS2812 | |
| GPIO22 | |
| buzzer | |
| GPIO9 | |
| I2C, SPI, UART, PWM, Analog | |
| Power | Micro USB |
| 18650 battery (sold separately) | |
| On-board 18650 charger (1000 mA charging current) | |
| size | 87×55×37mm |
WuKong 2040 setup
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There are no software libraries to install for WuKong 2040. This means you can access the GPIO directly through any compatible programming language. After inserting the Raspberry Pi Pico into the header pins, my first intuition was to connect the micro USB cable to the WuKong 2040’s micro USB port. This intuition was incorrect. This particular port appears to be reserved for charging the 186050 cell (not included).
Speaking of the 18650s, you should get a battery with a flat top instead of a tip for + polarity. Flat-top batteries will slide into place with minimal force, while other batteries will develop significant force on the spring steel contacts. please give me. They can store a lot of power and should not be damaged or shorted out. Store in a safe plastic container when not in use.
To write code to the Raspberry Pi Pico, I had to connect it to the micro USB port on the Pico itself. I’m not a big fan of this, as the number of plugging and unplugging cycles will eventually shorten the Pico’s lifespan. But that’s just the way it is.
The GPIO is split through a series of SVG (signal (yellow), voltage (red), and ground (black)) pins. This means that all connections have access to 3V and GND, which is convenient.
The true value is shown when the servo is attached. The SVG pinout matches the servos perfectly, allowing you to run up to 12 servos with a small amount of code. There are four motor terminals, M1 to M4. These terminals are connected to the Raspberry Pi Pico’s GPIO pin breakouts through four chips. The chip should be some form of H-bridge controller that can switch the polarity of the motors to provide forward and backward movement. But these 75V15 chips baffled me. I can’t find a datasheet for them. However, it works similarly to traditional H-bridge motor controllers (L298, L3110S, DRV8833, etc.). I hooked up two Lego-compatible DC motors and wrote a few lines of MicroPython to spin the robot around the desk.
The onboard Neopixels are bright and easy to use with MicroPython and CircuitPython. Elecfreaks suggested using his CircuitPython from Adafruit, so I used that for a quick test. I got stuck here too. I usually save my code in Pico as code.py. The NeoPixel library is in the lib folder and everything works. But it wasn’t. After some brainstorming, I found out that I had to swap out the micro USB port from the Pico to the WuKong 2040 to see the NeoPixels light up. This is not a great workflow and can cause problems for beginners.
lego compatible chassis
Underneath the mainboard is a lego compatible frame. This frame is designed to work with Technic components and is also compatible with Lego Spike components. I installed his two of his Lego compatible DC motors, which he bought for under $10 a pair from Aliexpress, and searched boxes for Lego Spike parts. 90% of the pieces we connected weren’t official Lego, but they were all well connected, official or not. The LEGO chassis integration is a key selling point. This means you can create your projects without needing the ultimate 3D printer or laser cutter.
What kind of projects can be created with the Wikong 2040?
First and foremost, this is a board for Pico robotics. It just works with robots. Put a Raspberry Pi Pico W on top, put in a 18650 battery, and learn Anvil, who has a Wi-Fi controlled robot.
Digital and analog GPIOs and specialized protocols also work well with the onboard battery system. It means you can build a sensor platform with a few parts, put it in a fancy case and start collecting data. Multiple servo connections make this board a fun board for building walking robots or sensor-triggered art installations that change gracefully.
Conclusion
For $10 you can forgive the micro USB problem. It’s certainly a hassle, but the sheer number of features and ease of use that the WuKong 2040 has puts you in a lot of fun. The onboard 18650 battery holder and charging system are convenient. It doesn’t give you a full GPIO breakout, but it’s good enough for my needs.
It may be helpful to print the GPIO pin reference on your board. It would have been nice if the I2C, SPI and UART pin references were also included. Lego compatible bases are great fun for Lego fans like me. If you don’t need it, don’t worry. Grab a Phillips screwdriver and it will pop right off. For classrooms, makerspaces, or do-it-yourself projects, the WuKong 2040 is a great all-rounder for $10.
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